//xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 
//三。使用钓子的dll 
//            1.参见我的QQ本马程序: 
// http://blog.gameres.com/thread.asp?BlogID=386&;threadid=13701;threadid=13701 
//            2.另一个用于按F3弹出dll框供输出debug信息的dll,代码如下: 
// 用vc创建一个win32dll,并在菜单中选择insert下的resource,插入一个dialog按ctrl+s存盘,并编写内容如下： 
// logdll.h内容: 
#ifdef LOGDLL_EXPORTS 
#define LOGDLL_API __declspec(dllexport) 
#else 
#define LOGDLL_API __declspec(dllimport) 
#endif 

extern "C" LOGDLL_API void LG( const char* szTxt ); 

// logdll.cpp 内容: 
// 
#include <windows.h> 
#include "logdll.h" 
#include "resource.h" 

// global data: 
#pragma comment( linker, "section:Shared,rws" ) 
#pragma data_seg( "Shared" ) 
HHOOK            g_hhook            = NULL; 
HINSTANCE g_hInstance = NULL; 
HWND             g_pLogDlg        = NULL; 
BOOL             g_bShowDlg     = FALSE; 
#pragma data_seg() 

//------------------------------------------------------------------------ 
void Init(); 
void Finish(); 
BOOL CreateLogDlg(); 
BOOL ShowLogDlg(); 
void InstallHook(); 
void UninstallHook(); 

LRESULT CALLBACK KeyboardProc( int, WPARAM, LPARAM ); 
INT_PTR CALLBACK LgDlgProc( HWND, UINT, WPARAM, LPARAM ); 


//------------------------------------------------------------------------ 
/* 
*/ 
BOOL CreateLogDlg() 
{ 
         if( g_pLogDlg ) return TRUE; 

if( FALSE == g_hInstance ) return FALSE; 

         g_pLogDlg = CreateDialog( g_hInstance, MAKEINTRESOURCE(IDD_DIALOG1), NULL, (DLGPROC)LgDlgProc ); 
return TRUE; 
} 
//------------------------------------------------------------------------ 
/* 
*/ 
BOOL ShowLogDlg() 
{ 
if( NULL == g_pLogDlg ) 
{ 
if( FALSE == CreateLogDlg() ) 
return FALSE; 
} 
         return ShowWindow( g_pLogDlg, (g_bShowDlg = !g_bShowDlg) ? SW_SHOW : SW_HIDE ); 
} 
//------------------------------------------------------------------------ 
/* 
*/ 
void InstallHook() 
{ 
if( g_hhook == NULL ) { 
g_hhook = SetWindowsHookEx( WH_KEYBOARD, (HOOKPROC)KeyboardProc, g_hInstance, 0 ); 
} 
} 
//------------------------------------------------------------------------ 
/* 
*/ 
void UninstallHook() 
{ 
if( g_hhook ) { 
UnhookWindowsHookEx(g_hhook); 
g_hhook = NULL; 
} 
} 


//------------------------------------------------------------------------ 
/* 
*/ 
LOGDLL_API void LG( const char* szTxt ) 
{ 
// here set the text info to your dialog's text ctrl 
} 
void Init() 
{ 
InstallHook(); 
} 
void Finish() 
{ 
UninstallHook(); 
if( g_pLogDlg ) 
{ 
DestroyWindow( g_pLogDlg ); 
g_pLogDlg = NULL; 
} 
} 
//------------------------------------------------------------------------ 
/* 
*/ 
BOOL APIENTRY DllMain( HANDLE hModule, DWORD ul_reason_for_call, LPVOID lpReserved ) 
{ 
g_hInstance = (HINSTANCE) hModule; 
         switch( ul_reason_for_call ) 
{ 
case DLL_PROCESS_ATTACH: 
Init(); 
break; 
case DLL_THREAD_ATTACH: 
Init(); 
break; 
case DLL_THREAD_DETACH: 
Finish(); 
break; 
case DLL_PROCESS_DETACH: 
Finish(); 
break; 
         } 
         return TRUE; 
} 
//------------------------------------------------------------------------ 
/* 
*/ 
LRESULT CALLBACK KeyboardProc(int nCode, WPARAM wParam, LPARAM lParam) 
{ 
LRESULT res = CallNextHookEx( g_hhook, nCode, wParam, lParam); 
if( (lParam & (1 << 31)) && (wParam == VK_F3) && (nCode == HC_ACTION) )    
{ 
ShowLogDlg(); 
} 
return res; 
} 
//------------------------------------------------------------------------ 
/* 
*/ 
INT_PTR CALLBACK LgDlgProc( HWND hDlg, UINT msg, WPARAM wParam, LPARAM lParam ) 
{ 
         switch ( msg ) 
         { 
                 case WM_INITDIALOG: 
                         return TRUE; 

                 case WM_COMMAND: 
                         switch( LOWORD(wParam) ) 
                         { 
                                 case IDCANCEL: 
                                 case IDOK: 
                                         EndDialog( hDlg, TRUE ); 
g_bShowDlg = FALSE; 
                                         return TRUE; 
                         } 
                         break; 

                 case WM_DESTROY: 
                         break; 
         } 

         return FALSE; 
} 

//xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 
// 四。不同语言混合编程方法 
//             标题太夸张了点，这里只是通过一种语言编写dll给另一种语言使用而已。例如：在VC中写dll而在vb中调用。这个在我转载的文章中已有祥细例子，我就不多说了，参见:（引用别人的“库”，又少写了很多“代码”，呵呵） 
     http://blog.gameres.com/thread.asp?BlogID=386&;threadid=13945 
//xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 


//xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 
// 五。插件dll相关撰写 
// (我写了以下例子来说明3dmax的导出插件是如何编写与实现, 
// 源码简单就不说明了) 
//xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 
这里我们的程序我用app.h和app.cpp实现，而别人写的插件我用plugtest.h与plugtest.cpp实现. 
1.先写我们的程序(用建立普通win32程序方法创建) 

// app.h头文件内容: 
#include <windows.h> 
// extern "C"    

// Define USING_IMPORT by app's project setting that this head file local at    
#ifdef USING_IMPORT 
#define THIS_CLASS_EXPORT __declspec(dllimport)    
#else 
#define THIS_CLASS_EXPORT __declspec(dllexport)    
#endif 

class THIS_CLASS_EXPORT TestExport    
{ 
public: 
                                    TestExport()     {}; 
virtual ~TestExport() {}; 
virtual int DoExport()         = 0; 
}; 

class THIS_CLASS_EXPORT ClassDesc    
{ 
public: 
virtual HINSTANCE HInstance() = 0; 
virtual void* Create()                 = 0; // { return new TestExport's Derive class } 
}; 

// app.cpp 文件内容: 
// 
#include "app.h" 
#include <stdio.h> 
#include <IO.H> 

typedef ClassDesc* (*PFN_DESC)(); 

void TestCall( const char* szName ) 
{ 
HINSTANCE hDll            = LoadLibrary( szName ); 
         PFN_DESC pPlugDesc = (PFN_DESC)GetProcAddress( hDll, "Get_PlugDesc" ); 

ClassDesc* pDesc = (*pPlugDesc)(); 
if( pDesc ) 
{ 
TestExport* pExp = (TestExport*)pDesc->Create(); 
if( pExp ) 
{ 
pExp->DoExport(); 
} 
} 
} 

int APIENTRY WinMain(HINSTANCE hInstance, 
                                            HINSTANCE hPrevInstance, 
                                            LPSTR            lpCmdLine, 
                                            int                nCmdShow) 
{ 

// search all dll: 
         struct _finddata_t c_file;    
         long hFile;    
/* Find first .c file in current directory */    
         if( (hFile = _findfirst( "*.dll", &c_file )) == -1L ) 
printf( "No *.dll files in current directory!\n" );    
else    
{    
TestCall( c_file.name ); 

/* Find the rest of the .c files */    
while( _findnext( hFile, &c_file ) == 0 )    
{    
TestCall( c_file.name ); 
}    
_findclose( hFile );    
} 

return 0; 
} 

下面写一个插件来测试一下: 
可在vc中用普通win32 dll的创建方法来创建以下一个dll内容: 
// plugtest.cpp内容 
// 
#include <windows.h> 
#include "../app/app.h" 

//#pragma comment(lib, "app.lib") 

HINSTANCE g_hInstance; 

// example:    
// notic: must not define USING_IMPORT(because this example using for client) 
class Dll_Plug : public TestExport 
{ 
int DoExport() 
{ 
MessageBox(0, "test ok", "ok", 0); 
return 1; 
} 
}; 
class Test_plusClassDesc : public ClassDesc 
{ 
HINSTANCE HInstance() 
{ 
return g_hInstance; 
} 
void* Create()                                 
{    
return new Dll_Plug; 
} 
}; 

static Test_plusClassDesc test_plusDesc; 

extern "C" THIS_CLASS_EXPORT ClassDesc* Get_PlugDesc()                                         
{    
return &test_plusDesc;    
} 

BOOL APIENTRY DllMain( HANDLE hModule,    
                                                DWORD     ul_reason_for_call,    
                                                LPVOID lpReserved 
) 
{ 
g_hInstance = (HINSTANCE)hModule; 
         return TRUE; 
}